Display device for telescope system

Abstract

A display device ( 4 ) for a telescope system is disposed between a first image plane ( 10 ) and a second image plane ( 20 ) of the telescope system. The display device includes a signal emitter ( 41 ), a converging lens group ( 42 ) positioned adjacent to the signal emitter, and a dioptric imaging lens group ( 43 ) positioned adjacent to the converging lens group. The optical signal emitted by the signal emitter is first transmitted through the converging lens group, then incident onto the dioptric imaging lens group, and finally imaged onto the second image after reflection of the dioptric imaging lens group. Therefore, both the image size and brightness of the displayed signal viewed by the observer can maintain unchanged in spite of the magnification variation of the telescope system.

1. A display device, being disposed between a first image plane and a second image plane of a telescope system, comprising:
 a signal emitter emitting a signal to be displayed in the form of a light beam; 
 a converging lens group positioned adjacent to the signal emitter for condensing the signal light beam emitted by the signal emitter; and 
 a dioptric imaging lens group positioned adjacent to the converging lens group, the dioptric imaging lens group comprising a dioptric prism and a trapezoidal prism, and the dioptric prism comprising a total reflection surface and a film-coating surface; 
 wherein the signal light beam emitted by the signal emitter is incident into the trapezoidal prism through the converging lens group, and the total reflection surface and the film-coating surface sequentially reflect the signal light beam onto the second image plane of the telescope system for imaging. 
 
   
   
     2. The display device as claimed in  claim 1 , wherein the trapezoidal prism and the dioptric prism are cemented with each other. 
   
   
     3. The display device as claimed in  claim 1 , wherein the total reflection surface and the film-coating surface of the dioptric prism are both surfaces at 45 degrees and are parallel with each other. 
   
   
     4. The display device as claimed in  claim 3 , wherein the film-coating surface of the dioptric prism partially reflects the wavelengths of the signal light beam. 
   
   
     5. The display device as claimed in  claim 4 , wherein the trapezoidal prism comprises an inclined incident surface facing the converging lens group. 
   
   
     6. The display device as claimed in  claim 5 , wherein the incident surface of the trapezoidal prism is inclined at an angle between negative 15 degrees and positive 15 degrees. 
   
   
     7. The display device as claimed in  claim 6 , wherein the converging lens group comprises a first converging lens of positive refractive power and a second converging lens of positive refractive power. 
   
   
     8. The display device as claimed in  claim 7 , wherein the first converging lens is a compound lens, and includes a convex-plano lens having a convex surface facing the signal emitter and a concave lens having a concave surface toward the signal emitter. 
   
   
     9. The display device as claimed in  claim 8 , wherein the second converging lens is a compound lens, and includes a concave lens having a concave surface facing away from the signal emitter and a plano-convex lens having a convex surface facing away from the signal emitter. 
   
   
     10. A telescope system having a first image plane and a second image plane, comprising:
 an objective system positioned at the front of the telescope system for receiving a light beam reflected from the target to be observed and then focusing and imaging the light beam onto the first image plane; 
 a magnification system positioned in the middle of the telescope system for magnifying, erecting and finally imaging the light beam from the first image plane onto the second image plane; 
 an eyepiece system positioned at the rear of the telescope system for allowing the observer to view the image on the second image plane; and 
 a display device positioned between the first image plane and the second image plane, and comprising a signal emitter for emitting a signal light beam, a converging lens group positioned adjacent to the signal emitter and a dioptric imaging lens group positioned adjacent to the converging lens group, wherein the dioptric imaging lens group comprises a dioptric prism and a trapezoidal prism, and the dioptric prism comprises a total reflection surface and a film-coating surface; 
 wherein the signal light beam emitted by the signal emitter is incident into the trapezoidal prism through the converging lens group, and the total reflection surface and the film-coating surface sequentially reflect the signal light beam onto the second image plane for imaging. 
 
   
   
     11. The telescope system as claimed in  claim 10 , wherein the trapezoidal prism and the dioptric prism are cemented with each other. 
   
   
     12. The telescope system as claimed in  claim 10 , wherein the total reflection surface and the film-coating surface of the dioptric prism are both surfaces at 45 degrees and are parallel with each other. 
   
   
     13. The telescope system as claimed in  claim 12 , wherein the film-coating surface of the dioptric prism partially reflects the wavelengths of the signal light beam. 
   
   
     14. The telescope system as claimed in  claim 13 , wherein the trapezoidal prism comprises an inclined incident surface facing the converging lens group. 
   
   
     15. The telescope system as claimed in  claim 14 , wherein the incident surface of the trapezoidal prism is inclined at an angle between negative 15 degrees and positive 15 degrees.